What Causes White Spots On The Vagina?

I asked this a few minutes ago, but my computer froze up

I have white spots on my vaginal opening. Most of the time it does not itch. They look like cottage cheese. I am assuming it's a yeast infection.

Would I be ok calling and asking for a prescription and seeing what happens, or do I need to be seen.

Also - the embarassing part can you get a yeast infection from sex, both oral and pentration?

Thanks